Treatment of iron or steel for preventing oxidation or rusting.



UNTTED RTATES PATENT @FRTQE.

rRAn'K RUPERT GRANVILLE RICHARDS, or COVENTRY, ENGLAND.

TREATMENT OF IRON R STEEL FOR PREVENTING OXIDATION 0R RUSTING.

N 0 Drawing.

Specification of Letters Patent.

Patented Aug12,1913.

Application filed August 15, 1912. I Serial No. 715,258.

. Improvements Relating to the Treatment of Iron or Steel for Preventing Oxidation or Busting, of which the following is aspecification,

In order to prevent oxidation or rusting it has been proposed to treatiron or steel with phosphoric acid and in some cases with a compoundconsisting of a dilute solution of ordinary phosphoric'acid and ironfilings or ferrous phosphate.

According to this invention the oxidation or rusting'of articlescomposed of iron or steel or having a surface of iron or steel isprevented by subjecting them to the action of manganese dioxid andphosphoric acid by which action a rust preventing deposit of manganeseand iron phosphates is formed thereon.

A solution in the following proportions has been found in practice to besatisfactory:

vLiquid concentrated ,phosphoric acid (1:5); 5 gallon Manganese dioxid 3lbs. Water- 120 gallons.

The solution is placed in a suitable bath or other receptacle and itstemperature raised to boiling point. The articles to be treated are thenwhile thoroughly clean, immersed therein for from thlrty to ninetyminutes as required according to the quality of the steel or iron undertreatment. After this treatment the articles may be dried and oiledpreparatory to use.

What I claim and desire to secure by Letters Patent of the United Statesis 1. The method of preventing the oxidization of iron or steel,consisting in forming thereon a rust-preventing deposit of manganese andiron phosphates by subjecting the metal to the action of manganesedioxid and phosphoric acid.

2. The method of preventing the oxidation of iron or steel, consistingin forming thereon a rust-preventing deposit of manganese and ironphosphates by subjecting the metal to the action of manganese dioxid andphosphoric acid in substantially the proportions of three pounds ofmanganese dioxid and one half gallon of phosphoric acid dissolved insubstantially one hundred and twenty gallons of water.

3. A solution or compound for preventing oxidation 'or rusting of ironor steel, com prising manganese dioxid, phosphoric acid, and water insubstantially the proportions of three pounds of the first, one halfgallon of the second, and one hundred and twenty gallons of the third.

In testimony whereof I aflix my signature in presence of two witnesses.

FRANK RUPERT GRANVILLE RICHARDS.

